Flydubai flight FZ981 was on manual control when the cockpit crew apparently sent it into a nosedive, resulting in a fatal crash in Russia, investigators have reported, citing flight recorder data. The plane hit the ground at 600kph and was at an angle of 50 degrees.

The flight records have been transcribed and provisionally analyzed, the Interstate Aviation Committee reported on Friday. The data showed that flight FZ981 made two landing approaches to Rostov-on-Don Airport, but on both attempts decided to cut short the process and perform a go-around maneuver. In both attempts the crew piloted the aircraft in manual mode.

The second approach was discontinued when the Boeing 737-800 was at 220 meters altitude, 4km from the runway. The crew switched engines into take-off mode and started ascending. They then apparently took a maneuver that resulted in the crash.

“At the altitude of 900 meters the crew pushed the yoke and at the same time a stabilizer was moved five degrees into nosedive position, which resulted in a rapid descent and a vertical acceleration of up to -1g,” the report said. “The consequent actions of the crew failed to prevent the aircraft’s collision with the ground. The collision happened at a speed of over 600 kmh and pitch angle of over 50 degrees.”

The committee said it is working on a full reconstruction of the disaster, with expert pilots from the US and the UAE contributing to the work. It is also working on transcribing the full two-hour voice recording form the cabin. The crew members communicated in English and Spanish, so the investigators are planning to use aviation experts from Spain to ensure accurate identification and transcription of the tape.

The investigators are yet to voice any official comments on the cause of the fatal incident, which claimed the lives of 62 passengers and crew members on March 19. Sources close to the probe, who spoke to the Russian media on condition of anonymity, said that pilot error is the most likely explanation for the cause of the crash.

Earlier, RT reported that numerous Flydubai pilots have been complaining for years that the airline uses exhausting rosters and turns a blind eye to employee complaints. Pilot fatigue could have been a contributing factor in the Rostov-on-Don crash, some of the whistleblowers told RT.